Container safety closure



Nov. 15, 1960 w. J. CHRISTIE 2,960,247

CONTAINER SAFETY CLOSURE Filed March 10, 1958 HELIX OF THREADS WILLIAM J. CHRISTI INVEN HIS ATTORNEY CONTAINER SAFETY CLOSURE William John Christie, 1420 S. Troost, Tulsa, Okla, assignor of fifty-one percent to J. T. Olson, Tulsa, Okla.

Filed Mar. 10, 1958, Ser. No. 720,376

7 Claims. (Cl. 215-9) This invention relates to an apparatus for opening and closing containers. More particularly it relates to a novel cap and thread relief design for containers having dangerous or special materials therein.

The purpose of this invention is to provide an identification means for containers with dangerous or poisonous substances therein; i.e., the container neck and associated cap design of this invention, and its corresponding method of use, will serve as a warning or marker to the user that the contents are of dangerous propensities or are of special significance.

Containers of the prior art and those in use today have conventional means for opening and closing the container. Typically, a threaded means is used to fasten a closure or cap to a container. The threads, however, are usually right-hand threads; i.e., the cap advances to the right or clockwise when engaged with the threads of the container to close an opening of the container. The cap is removed by the reverse procedure. Such a closing procedure, being so conventional and common, results in accidental usage in many instances. For example, the contents of medicinal containers in domestic use may, in the course of events, fall into accidental usage by individuals, resulting in violent illness and even death.

Accordingly, it is an object of this invention to provide a container opening and closing means which overcomes the objections to presently used devices.

It is another object of this invention to provide a container opening and closing means which acts as a warning to the user that the contents therein are of a special nature.

It is a further object of this invention to provide a threaded opening and closing means for containers which is of significant difierence from conventional threaded means that it will serve as a warning of the contents therein.

It is a still further object of this invention to provide a container cap with integral rightand left-hand threaded portions in association with novel thread followers on the container.

Additional objects of the present invention will become apparent upon reading the following specification and referring to the accompanying drawings, in which:

Figure l is a sectional view of a cylindrical container cap for use according to this invention.

Figure 2 is a front elevational view of the neck of a container with the thread follower embodiment of this invention.

Figure 3 is a sectional view taken along the line 33 of Figure 1.

Figure 4 is a sectional view taken along the line 4-4 of Figure 2.

Figure 5 is an elevational view of an additional embodiment of this invention.-

Figure 6 is a sectional view taken along the line 6-6 of Figure 5.

Referring specifically to Figure l, 10 represents the States atent safety cap of this invention which is composed of either metal, synthetic resins or plastics, glass, polyethylene, or combinations thereof. The cap is formed by machining, extrusion processing, molding, or by a die casting process, depending to a large extent upon the particular material used. As indicated by the drawing, the internal portion of the cap defines an opening 12 and cylindrical recess 14. Adjoining recess 14 is internal threaded portion 16, preferably of the knuckle style of thread form as shown. However, this is not to be limiting, as any of the wellknown screw-thread forms may be used. The threads are, for example, right-hand threads and extend for a lead or axial advance sufficient for steady contact with thread followers 28 and 29 on the container. Preferably, there is sufiicient thread to result in at least one revolution of cap 10. Immediately adjacent threaded portion 16 is an internal relief cylinder 18 which is not threaded, but has a diameter at least equal to the major diameter of threads 16. The length of cylinder 18 is at least equal to, but preferably slightly larger than, twice the pitch of thread 16. The pitc as used herein and in the appended claims is defined by American Standard Screw Threads as the distance from a point on a screw thread to a corresponding point on the next thread measured parallel to the axis. Immediately adjacent internal relief cylinder 18 and away from opening 12 is threaded portion 20 having its thread direction in opposition to threads 16; yet, threaded portions 16 and 20 are of equal form or thread dimension. Specifically, as shown, the threads 20 are left-hand threads having the same pitch, major and minor diameter, thread shape, and helix angle as the threads 16. Threads 20 extend for a lead sufficient to make stable contact with thread followers 28 and 29 described hereinafter. At the farthermost point from opening 12 is the internal end stop 22 and optional recess 23 which seal the container opening.

Referring now to Figure 2, 24 represents a container which may be composed of any of the materials above suggested for cap 10. A cylindrical neck portion 26 is connected to the container as a part thereof. The length of the neck portion must be at least equal to the length of the associated cap 10 or the distance from opening 12 to end stop 22 of the internally threaded and relief portion. The outside diameter of neck portion 26 is equal to, or slightly smaller than, the minor diameter or smallest diameter of threads 16 and 20. Attached to the neck portion and extending outward therefrom are thread followers 28 and 29. The followers as shown have a hemispherically shaped crest to match the root portion of in ternal knuckle threads 16 and 20 of cap 10 to permit steady rotative movement. The followers are positioned on the neck portion along a line corresponding to the helix of the threads 16 and 20 formed in the cap 10. The followers are spaced apart circumferentially as illustrated more clearly in Figure 4. The term helix as used herein and in the appended claims shall mean that which is generated by a point moving around and along the surface of a cylinder at a given angle.

The position of follower 28 is preferably adjacent top 30 as shown.

An additional embodiment to the present invention is described with reference to Figures 5 and 6. It is within the purview of this invention to use only one thread follower 28 positioned on the outside of neck portion 26' and substantially adjacent top 30'.

In using the safety closure of this invention, as illus trated in Figures 1 through 4, cap 10 is placed with opening 12 and recess .14 over the neck portion 26 of container 24. Engagement is made between the followers 28 and 29 with the internal threaded portion 16 by turning the cap and/or container in a right-hand or clockwise direction. Further rotation will advance cap 10 downward until followers 28 and 29 have cleared threads 16 and entered the relief cylinder 18. Continued righthand rotation will not advance the cap further due to left-hand threads 20. Since cylinder 18 is slightly larger than twice the pitch of threads 16 and 20, the cap will drop slightly. counterclockwise rotation of cap will engage the followers with left-hand threads 20 causing additional advance of cap 10 until the end stop 22 mates with the top of neck 26 to effectively seal the contents in container 24.

Removal of the cap in the previous example is effected by a first clockwise rotative motion of the cap and/or the followers until engagement with the relief cylinder portion. The cap is then lifted to engage the followers with threads 16. Further rotation after engagement in a counterclockwise direction will remove the cap.

It is within the purview of this invention that the above procedure will be reversed when threads 16 are left hand threads and threads 20 are right-hand threads. The position of followers 28 and 29 will remain unchanged; only the rotation steps will be changed.

It can be readily seen that the container closure system of this invention comprises three important structural features, namely:

(1) A container neck portion with at least one, and not more than two, thread followers which extend along the helix line of the thread system, yet are spaced 180 apart,

(2) A cap with right-hand and left-hand threads, and

(3) A relief cylinder spaced between the aforesaid right-hand and left-hand thread portions, the length of the cylinder to be slightly larger than twice the pitch of the thread system.

While I have illustrated and described the preferred embodiments of my invention, it is understood that I do not limit myself to the precise construction herein disclosed. For example, followers 2 8 and 29 may be constructed of other thread forms than the knuckle style as illustrated. Thread forms such as the sharp-V or American standard may be used. These and other changes will come within the scope of the invention as defined in the appended claims.

I claim:

1. A removable safety cap for closing containers comprising an open and closed end, equal form internal righthand threaded portion and a left-hand threaded portion between said open and closed end, an internal relief cylinder spaced between said right-hand threaded portion and said left-hand threaded portion, said cylinder having a maximum diameter equal to the maximum diameter of said internal threaded portions and a depth slightly greater than two times the pitch of said internal threaded portion.

2. A safe opening closure for a container comprising in combination a cap with equal form internal right-hand and left-hand screw threads and an internal relief cylinder spaced between said rightand left-hand threads, said cap adapted to be threadably removed and secured to a neck portion on said container by a first thread follower on said neck portion and a second thread follower on said neck portion circumferentially spaced from said first follower along a line generated by the helix of said threads.

3. A safe opening closure for a container comprising in combination a cap with equal form internal right-hand and left-hand screw threads and an internal relief cylinder pac d. be ween sa d ig and eft-h nd thr Said p adap ed to e hr adably r e nd s ur d to a ne k por ion on said, con ainer by a first threa f lower on said neck portion and a second thread follower on said neck portion circumferentially spaced 180 from said first follower along a line generated by the helix of said threads for one-half revolution.

4. A safe opening closure according to claim 3 wherein said threads are a knuckle form of screw thread.

5. A safe opening closure according to claim 3 wherein said relief cylinder is of a diameter equal to at least the maximum diameter of said threads and of a depth equal to at least two times the pitch of said threads.

6. A safe opening closure according to claim 5 wherein said relief cylinder is of a diameter equal to at least the maximum diameter of said threads and a depth equal to at least the pitch of said threads.

7. A safe opening closure for containers comprising in combination a cap with equal form internal righthand and left hand screw threads and an internal relief cylinder spaced between said right-hand and left-hand threads, said cap adapted to be threadably removed and secured to a neck portion on said container by a thread follower on said neck.

References Cited in the file of this patent UNITED STATES PATENTS 699,606 Wilson May 6, 1902 774,014 Wilson Nov. 1, 1904 837,648 Elfstrom Dec. 4, 1906 1,279,223 Barry Sept. 17, 1918 FO E G ATE TS 532,266 Canada Oct. 30, 1956 1,108,212 France Oct. 24, 1955 

